Dubois Anna, Rajan Neil
Department of Dermatology Royal Victoria Infirmary Newcastle upon Tyne, UK
cutaneous syndrome (CCS) typically manifests in the second or third decade with the appearance of multiple skin tumors including cylindromas, spiradenomas, trichoepitheliomas, and rarely, membranous basal cell adenoma of the salivary gland. The first tumor typically develops at puberty and tumors progressively accumulate through adulthood. Females often have more tumors than males. Tumors typically arise on the scalp and face but can also arise on the torso and sun-protected sites, such as the genital and axillary skin. A minority of individuals develop salivary gland tumors. Rarely, pulmonary cylindromas can develop in large airways and compromise breathing. Although the tumors are usually benign, malignant transformation is recognized.
DIAGNOSIS / TESTING: The diagnosis of cutaneous syndrome is established in a proband with multiple skin tumors (histologically confirmed cylindromas, spiradenomas, and/or trichoepitheliomas) and/or by identification of a germline heterozygous pathogenic variant in by molecular genetic testing.
Removal of cylindromas, spiradenomas, and trichoepitheliomas is by conventional surgery. Ideally, as much normal scalp and skin should be preserved. "Scalp-sparing" strategies include early primary excision with direct skin closure, tumor enucleation followed by direct skin closure, and excision followed by secondary intention healing techniques. Hyfrecation or laser ablation of selected small tumors may be considered. Mohs micrographic surgery for recurrence of tumors after failure of primary surgical excision may have limited benefit. Multidisciplinary team management of tumors that have undergone malignant transformation is recommended. Appropriate precautions against UV-related skin damage are recommended. : Annual or more frequent full skin examination by a dermatologist, with assessment of tumor burden and rate of new tumor development, and for signs/symptoms of malignant transformation (rapid tumor growth, bleeding, ulceration, or appearance that is different from an affected individual's usual tumors). Radiotherapy should be avoided as it causes DNA damage and may result in further tumor formation or malignant transformation of existing lesions. It is appropriate to clarify the genetic status of apparently asymptomatic older and younger at-risk relatives of an affected individual in order to identify as early as possible those who would benefit from prompt initiation of treatment and preventive measures.
Germline pathogenic variants in are inherited in an autosomal dominant manner. Most individuals with cutaneous syndrome inherit it from a parent. The degree of severity can vary within families; for example, a mildly affected parent may have a more severely affected child or vice versa. Offspring of an individual with cutaneous syndrome have a 50% chance of inheriting the variant. Prenatal testing for a pregnancy at increased risk is possible if the pathogenic variant in the family is known; however, requests for prenatal testing for later-onset diseases are uncommon and require careful genetic counseling.
皮肤综合征(CCS)通常在二三十岁时出现,表现为多种皮肤肿瘤,包括圆柱瘤、汗腺螺旋腺瘤、毛发上皮瘤,很少见的还有涎腺膜性基底细胞腺瘤。首个肿瘤通常在青春期出现,肿瘤在成年期逐渐累积。女性的肿瘤通常比男性多。肿瘤通常出现在头皮和面部,但也可能出现在躯干以及防晒部位,如生殖器和腋窝皮肤。少数个体可发生涎腺肿瘤。罕见情况下,大气道可出现肺圆柱瘤并影响呼吸。虽然这些肿瘤通常是良性的,但也存在恶变情况。
诊断/检测:皮肤综合征的诊断基于先证者存在多个皮肤肿瘤(经组织学证实为圆柱瘤、汗腺螺旋腺瘤和/或毛发上皮瘤),和/或通过分子遗传学检测鉴定出种系杂合致病性变异来确定。
圆柱瘤、汗腺螺旋腺瘤和毛发上皮瘤通过传统手术切除。理想情况下,应尽量保留正常的头皮和皮肤。“保留头皮”策略包括早期一期切除并直接缝合皮肤、肿瘤剜除后直接缝合皮肤,以及切除后采用二期愈合技术。对于某些较小的肿瘤,可考虑使用高频电灼或激光消融。对于一期手术切除失败后肿瘤复发,Mohs显微外科手术的益处可能有限。对于发生恶变的肿瘤,建议进行多学科团队管理。建议采取适当措施预防紫外线相关的皮肤损伤。由皮肤科医生进行每年一次或更频繁的全面皮肤检查,评估肿瘤负担和新肿瘤的发生速率,以及恶变的体征/症状(肿瘤快速生长、出血、溃疡或外观与患者通常的肿瘤不同)。应避免放疗,因为它会导致DNA损伤,可能导致进一步的肿瘤形成或现有病变的恶变。明确受影响个体明显无症状但有风险的老年和年轻亲属的基因状态是合适的,以便尽早确定那些将从及时开始治疗和预防措施中受益的人。
种系致病性变异以常染色体显性方式遗传。大多数患有皮肤综合征的个体是从父母那里遗传而来。家族内严重程度可能不同;例如,症状较轻的父母可能有症状更严重的孩子,反之亦然。患有皮肤综合征的个体的后代有50%的机会遗传该变异。如果家族中的致病性变异已知,对于风险增加的妊娠可进行产前检测;然而,对于迟发性疾病的产前检测请求并不常见,需要仔细的遗传咨询。